As known, an adapter for a SIM card is a plastic frame on which a SIM card is applied or mounted for facilitating the plugging in of the SIM card in a SIM slot of a reader. In this respect, SIM cards having different sizes are available and currently manufactured, but readers include only one SIM slot and they are generally structured to receive a SIM card with a predetermined standard size.
For example, according to a standard ETSI TS 102 221, there are only a few currently worldwide accepted standard sizes, for instance: a 2FF SIM card (Plug-in UICC) has a size of 25 mm×15 mm and a thickness of 0.76 mm; a 3FF SIM card (Mini-UICC) has a different size of 15 mm×12 mm and a thickness of 0.76 mm; and a more recent 4FF SIM card (micro-UICC) has a different size of 11.9×8.8 mm and a different thickness of 0.67 mm. Thus, in the 4FF SIM card, not only the width and length of the card are reduced with respect to 2FF and 3FF SIM cards, but also the thickness.
FIGS. 1a-1c are top views of those 2FF, 3FF and 4FF standard SIM cards, respectively. The inner part of each figure represents a microchip and the portion delimited by dashed lines represents the support in which the microchip is packaged.
FIGS. 2 and 3 schematically represent in more detail the form factors of a so called Plug-in UICC and Mini-UICC according to the above mentioned standard ETSI TS 102 221, and FIG. 4 schematically represents the form factor of a so called micro-UICC according to the specification SCP(12)000007.
On the other hand, some readers have a 2FF slot adapted to receive only a 2FF SIM card, i.e. unable to receive a 3FF or 4FF SIM card because they are too large. Some other readers have a 3FF slot for a 3FF card which is unable to receive a 4FF SIM card, because it is too large. More recent readers have a 4FF slot adapted to read only the 4FF SIM card.
In view of the above, it has been common to use adapters that have been designed to adapt the different SIM cards to different slots of the readers.
An adapter is normally structured with a plastic frame having a same size as the slot wherein it is inserted and delimits an inner and empty space wherein the SIM card is received. Along the inner perimeter of the frame, some tongues or tabs are provided to support the SIM card within such an empty space.
For example, with reference to the examples of FIGS. 5b and 5c, a 2FF adapter has a central empty space or hole for receiving a 3FF SIM card (FIG. 5c) or a 4FF SIM card (FIG. 5b) and a plastic frame (outer perimeter) of a size substantially corresponding to a size of the 2FF slot. Similarly, FIG. 5a represents a 3FF adapter having a hole for receiving a 4FF SIM card and a plastic frame of a size corresponding to a size of the 3FF slot.
These adapters have some drawbacks. They may be easily lost due to their small size, which corresponds to the size of the slot of the reader, as explained above. Moreover, they are fragile, since the tongues T along the inner perimeter of the frame may be easily broken and when broken, the 4FF SIM can no longer be supported in the hole of the plastic frame and thus within the SIM slot.
Furthermore, the telecom operators or SIM card providers may desirably be provided with an adapter for each 4FF SIM card they sell, but this does not always happen, since the adapters are produced separately from the SIM card. In this respect, the production cost may be high, since the manufacturing process of the adapters of FIG. 5a-5c is different, not scaled and independent from the manufacturing process of the SIM cards of the samples shown in FIG. 1a-1c, for example, from the manufacturing process resulting in the 4FF SIM card plastic support represented in FIG. 6, which includes the 4FF SIM card to be adapted, integrated in the plastic support, according to the prior art.
The problem to be addressed by the present embodiments is thus to reduce the production costs, improve the robustness of the adapters, for example, when used within a slot or when stocked outside it, and to help in avoiding misplacing the adapters, thus overcoming the above mentioned disadvantages and limitations.